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Partial researchResearch snapshot 2026-09-13. Evidence gaps remain; see Coverage for requirements.

Office briefing

PIEDRAS NEGRAS — Municipal government

Tracked current office. Identifiers stay separate from display names.

Mexico · PIEDRAS NEGRAS / COAHUILA · municipal · Municipal governmentMX-M-5-25

Read the complete original research briefing

INE result distributions kept separate. Certified seats, supplementary elections, coalition and boundary audit remain.

1. What office, where, and when is the next election?

Geography
PIEDRAS NEGRAS / COAHUILA
Next election
2027-06-06
Linked upcoming event
next-b6688d8666a789af8b7107cd
Registry qualification
Unknown

2. How certain is that date?

2027-06-06 is expected (not formally called). Day precision. A date without a formal call is not confirmed.

3. Who won earlier selected elections?

2024

Special · Legal certification not established · candidate marks

  • PT_MORENA48.6%
  • PRI_PRD_UDC42.5%
  • MC3.6%
  • PVEM1.2%
  • PAN0.9%
Results for event-eaef843a4480d434fd5d587d
Label / candidateParty codeVotesShareSeatsStatus
PT_MORENAmexico/Sf4f0ddc91c/202442,30348.6%UnknownRecorded
PRI_PRD_UDCmexico/Sf4f0ddc91c/202437,02242.5%UnknownRecorded
MCmexico/Sf4f0ddc91c/20243,1763.6%UnknownRecorded
PVEMmexico/Sf4f0ddc91c/20241,0051.2%UnknownRecorded
PANmexico/Sf4f0ddc91c/20247450.9%UnknownRecorded

2021

Special · Legal certification not established · candidate marks

  • PRI_PRD29.3%
  • MORENA27.9%
  • PT24.9%
  • CAND_IND611.2%
  • PAN1.9%
  • PVEM0.9%
  • PES0.7%
  • FXM0.5%
  • RSP0.5%
  • MC0.4%
  • CAND_IND50.4%
Results for event-88400846cc5441dd7bec6bc4
Label / candidateParty codeVotesShareSeatsStatus
PRI_PRDmexico/Sfd0a26c170/202118,93329.3%UnknownRecorded
MORENAmexico/Sfd0a26c170/202118,05027.9%UnknownRecorded
PTmexico/Sfd0a26c170/202116,08624.9%UnknownRecorded
CAND_IND6mexico/Sfd0a26c170/20217,24111.2%UnknownRecorded
PANmexico/Sfd0a26c170/20211,2491.9%UnknownRecorded
PVEMmexico/Sfd0a26c170/20215840.9%UnknownRecorded
PESmexico/Sfd0a26c170/20214800.7%UnknownRecorded
FXMmexico/Sfd0a26c170/20213040.5%UnknownRecorded
RSPmexico/Sfd0a26c170/20212930.5%UnknownRecorded
MCmexico/Sfd0a26c170/20212820.4%UnknownRecorded
CAND_IND5mexico/Sfd0a26c170/20212450.4%UnknownRecorded

2018

Special · Legal certification not established · candidate marks

  • PT_MORENA_ES47.6%
  • PRI_PVEM_PANAL32.6%
  • PAN_UDC_MC15.6%
  • CAND_IND72.0%
  • PRD0.7%
Results for event-30084e7044159145005ed654
Label / candidateParty codeVotesShareSeatsStatus
PT_MORENA_ESmexico/Sb51ef83fd1/201833,00747.6%UnknownRecorded
PRI_PVEM_PANALmexico/Sb51ef83fd1/201822,57232.6%UnknownRecorded
PAN_UDC_MCmexico/Sb51ef83fd1/201810,78615.6%UnknownRecorded
CAND_IND7mexico/Sb51ef83fd1/20181,4052%UnknownRecorded
PRDmexico/Sb51ef83fd1/20184650.7%UnknownRecorded

4. Competition and volatility

competition index

Provisional imported-series CI

71.470–100 historical closeness

Actual-event and/or comparability review incomplete

Comparison status: Provisional imported-series comparison; actual-event review open

Method ci.weighted-gap.v1. Inputs: latest_gap=6.26817485845865, oldest_gap=15.292738330768664, previous_gap=1.3851632233673747

pedersen volatility

Provisional volatility

54.62percentage points

Grouped Pedersen lower bound (percentage points). Seven exact standalone INE party labels. Joint coalition combinations, independents and other parties remain Other, without allocating coalition votes. This coarse grouped comparison can conceal coalition-member shifts and requires the stated geographic/event review. An interval is withheld if either election has no list mapped to an explicit named group. This is aggregate share change, not individual voter switching. Event review: Actual-event and/or comparability review incomplete

Comparison status: Latest interval

Method pedersen.grouped.v1. Inputs: groups=["PAN","PRI","PRD","PT","PVEM","MC","MORENA","Other"], interval=Latest interval, vectors=[[0.8842625013352957,0,0,0,1.1928641796536539,3.769688193611945,0,94.1531851253991],[1.959307888998698,0,0,25.234128664878348,0.9161215429745714,0.44237375876511836,28.315057963512007,43.13301018087126],[0,0,0.6814684546054078,0,0,0,0,99.31853154539459]]

pedersen volatility

Provisional volatility

56.87percentage points

Grouped Pedersen lower bound (percentage points). Seven exact standalone INE party labels. Joint coalition combinations, independents and other parties remain Other, without allocating coalition votes. This coarse grouped comparison can conceal coalition-member shifts and requires the stated geographic/event review. An interval is withheld if either election has no list mapped to an explicit named group. This is aggregate share change, not individual voter switching. Event review: Actual-event and/or comparability review incomplete

Comparison status: Previous interval

Method pedersen.grouped.v1. Inputs: groups=["PAN","PRI","PRD","PT","PVEM","MC","MORENA","Other"], interval=Previous interval, vectors=[[0.8842625013352957,0,0,0,1.1928641796536539,3.769688193611945,0,94.1531851253991],[1.959307888998698,0,0,25.234128664878348,0.9161215429745714,0.44237375876511836,28.315057963512007,43.13301018087126],[0,0,0.6814684546054078,0,0,0,0,99.31853154539459]]

pedersen volatility

Provisional volatility

55.75percentage points

Grouped Pedersen lower bound (percentage points). Seven exact standalone INE party labels. Joint coalition combinations, independents and other parties remain Other, without allocating coalition votes. This coarse grouped comparison can conceal coalition-member shifts and requires the stated geographic/event review. An interval is withheld if either election has no list mapped to an explicit named group. This is aggregate share change, not individual voter switching. Event review: Actual-event and/or comparability review incomplete

Comparison status: Both intervals mean

Method pedersen.grouped.v1. Inputs: groups=["PAN","PRI","PRD","PT","PVEM","MC","MORENA","Other"], interval=Both intervals mean, vectors=[[0.8842625013352957,0,0,0,1.1928641796536539,3.769688193611945,0,94.1531851253991],[1.959307888998698,0,0,25.234128664878348,0.9161215429745714,0.44237375876511836,28.315057963512007,43.13301018087126],[0,0,0.6814684546054078,0,0,0,0,99.31853154539459]]

Source-reported control: Unverified. Current tenure requires separate dated evidence.

5. Officeholder evidence

Dated roster observations are not automatically current tenure. The source current-office flag means this office is tracked now, not that the last winner still holds it.

No officeholder observation supplied.

6. Polling context

No local poll supplied.

7. Unresolved issues and sources

No open research issues attached to this office.

Sources

Cite this record

Center for Digital Democracy. “PIEDRAS NEGRAS — Municipal government.” Subnational Election Observatory, releaselatin-america-fe5e91689def, snapshot 2026-09-13. /electiondatabase/offices/MX-M-5-25. Sources: mexico--url-3635e08ffbefd711526cbeea, mexico--Sf4f0ddc91c, mexico--Sfd0a26c170, mexico--Sb51ef83fd1.