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

Office briefing

ALTAMIRA — Municipal government

Tracked current office. Identifiers stay separate from display names.

Mexico · ALTAMIRA / TAMAULIPAS · municipal · Municipal governmentMX-M-28-3

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
ALTAMIRA / TAMAULIPAS
Next election
2027-06-06
Linked upcoming event
next-f3ddfda4b34afd343de9c59e
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_PVEM_MORENA70.3%
  • PAN_PRI18.1%
  • PRD4.8%
  • MC4.2%
Results for event-67e7edf458fc133026a41562
Label / candidateParty codeVotesShareSeatsStatus
PT_PVEM_MORENAmexico/S12095d74c8/202470,07470.3%UnknownRecorded
PAN_PRImexico/S12095d74c8/202418,09018.1%UnknownRecorded
PRDmexico/S12095d74c8/20244,8214.8%UnknownRecorded
MCmexico/S12095d74c8/20244,2224.2%UnknownRecorded

2021

Special · Legal certification not established · candidate marks

  • PT_MORENA43.8%
  • PAN39.5%
  • PRI4.7%
  • PES3.3%
  • PRD2.5%
  • MC1.7%
  • RSP0.7%
  • PVEM0.6%
  • FXM0.5%
Results for event-53d281576f17a3b94c0037de
Label / candidateParty codeVotesShareSeatsStatus
PT_MORENAmexico/Sf33764ddb7/202140,82743.8%UnknownRecorded
PANmexico/Sf33764ddb7/202136,75639.5%UnknownRecorded
PRImexico/Sf33764ddb7/20214,4164.7%UnknownRecorded
PESmexico/Sf33764ddb7/20213,0373.3%UnknownRecorded
PRDmexico/Sf33764ddb7/20212,3512.5%UnknownRecorded
MCmexico/Sf33764ddb7/20211,6081.7%UnknownRecorded
RSPmexico/Sf33764ddb7/20216310.7%UnknownRecorded
PVEMmexico/Sf33764ddb7/20215980.6%UnknownRecorded
FXMmexico/Sf33764ddb7/20214910.5%UnknownRecorded

2018

Special · Legal certification not established · candidate marks

  • PAN_PRD_MC41.7%
  • PT_MORENA_ES30.1%
  • PRI21.2%
  • PVEM2.8%
  • PANAL1.5%
Results for event-74e619720715470fe969e563
Label / candidateParty codeVotesShareSeatsStatus
PAN_PRD_MCmexico/S6f6ad63601/201842,46441.7%UnknownRecorded
PT_MORENA_ESmexico/S6f6ad63601/201830,59630.1%UnknownRecorded
PRImexico/S6f6ad63601/201821,56621.2%UnknownRecorded
PVEMmexico/S6f6ad63601/20182,8652.8%UnknownRecorded
PANALmexico/S6f6ad63601/20181,4911.5%UnknownRecorded

4. Competition and volatility

competition index

Withheld

Unknown0–100 historical closeness

Actual-event and/or comparability review incomplete

Comparison status: Comparison unavailable · INE result distributions kept separate. Certified seats, supplementary elections, coalition and boundary audit remain.

Method ci.weighted-gap.v1. Inputs: latest_gap=53.47763021181602, oldest_gap=null, previous_gap=4.487681199360637

pedersen volatility

Provisional volatility

46.05percentage 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=[[0,0,4.959519376176613,0,0,4.343308609462282,0,90.6971720143611],[40.518106156644436,4.867993165408146,2.591633136746955,0,0.6592074078156865,1.7725844678388358,0,49.590475665545945],null]

pedersen volatility

Withheld volatility

Unknownpercentage 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 · Comparable grouped vectors unavailable for this interval

Method pedersen.grouped.v1. Inputs: groups=["PAN","PRI","PRD","PT","PVEM","MC","MORENA","Other"], interval=Previous interval, vectors=[[0,0,4.959519376176613,0,0,4.343308609462282,0,90.6971720143611],[40.518106156644436,4.867993165408146,2.591633136746955,0,0.6592074078156865,1.7725844678388358,0,49.590475665545945],null]

pedersen volatility

Withheld volatility

Unknownpercentage 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 · Comparable grouped vectors unavailable for this interval

Method pedersen.grouped.v1. Inputs: groups=["PAN","PRI","PRD","PT","PVEM","MC","MORENA","Other"], interval=Both intervals mean, vectors=[[0,0,4.959519376176613,0,0,4.343308609462282,0,90.6971720143611],[40.518106156644436,4.867993165408146,2.591633136746955,0,0.6592074078156865,1.7725844678388358,0,49.590475665545945],null]

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

  • other · open

    Reconciliation required: {"id": "MX-M-28-3", "year": 2018, "issue": "Reconciliation required", "total_delta": -99.0, "duplicate_actor": false, "segments": 1}

Sources

Cite this record

Center for Digital Democracy. “ALTAMIRA — Municipal government.” Subnational Election Observatory, releaselatin-america-fe5e91689def, snapshot 2026-09-13. /electiondatabase/offices/MX-M-28-3. Sources: mexico--url-3635e08ffbefd711526cbeea, mexico--S12095d74c8, mexico--Sf33764ddb7, mexico--S6f6ad63601.