One of the Republican appointees to the Electoral College abruptly resigned from her post Thursday after publicly questioning whether she would support the party’s presidential ticket when casting official votes after the November election.

Melinda Wadsley of Ames, Iowa, told The Associated Press that she could not in good conscience vote for party nominee Mitt Romney. Wadsley was among three electors who had told the AP for a story published Thursday that they were exploring alternatives should Romney win their states.

‘‘I have always been a straight ticket Republican, and for the first time in my life I am an undecided voter, therefore, I need to resign my position as a Republican presidential elector,’’ Wadsley said in an email exchange.

Iowa GOP Chairman A.J. Spiker said in a statement that the state party’s central committee would begin the process of selecting a replacement, essentially allowing the party to confirm a die-hard Romney supporter.

Wadsley and others had expressed frustration at how Republican leaders have worked to suppress Paul’s conservative movement and his legion of loyal supporters.

‘‘They've never given Ron Paul a fair shot, and I'm disgusted with that. I'd like to show them how disgusted I am,’’ Wadsley had told the AP earlier, saying she was considering withholding her electoral vote from Romney. She is an Iowa mother of three who was selected as a Republican elector earlier this year and said Paul was the better choice.

She had also noted that the Electoral College was founded with the idea that electors wouldn’t just mimic the popular vote.

The defection of multiple electors would be unprecedented in the last 116 years of U.S. politics. It also would raise the remote possibility that the country could even end up with a president and vice president from different parties.

If Romney prevailed in an extremely close presidential election, for example, defections could deprive him of the Electoral College majority needed to secure the presidency. That would throw the presidential election to the U.S. House for the first time in nearly two centuries. The Senate would elect the vice president if neither running mate got a majority of the electoral votes. If Republicans retained control of the House, and with the each state delegation getting a single vote, Romney probably would prevail. But if the Senate remained in Democratic hands, Vice President Joe Biden would be the favorite.

Because so-called faithless electors are rare, the position of elector is largely viewed as symbolic. Each party chooses people to serve as electors in the 50 states, and electors from the winning party convene in each state capital in December to officially select the president and vice president.

As Paul supporters fought for more prestigious delegate slots during state-level conventions this year, they also quietly accrued electors — some in Democratic states likely to be won by President Barack Obama, but also in a handful in states that Romney could take.

In Nevada, for example, Paul’s forces seized control of the state convention and won a majority of delegates. They also placed four Paul supporters among the state’s six electors.

The electors said they have had no organized discussion over how to cast their electoral votes and there have been no efforts by the campaigns to get them to vote for either Paul or Romney.

Nevada’s electors are approaching their duties in different ways.

Jesse Law, an elector and Paul supporter, said he may have qualms with Romney but has always intended to cast his electoral vote for the party nominee.

‘‘I just want to beat Obama,’’ Law said.

But Ken Eastman may not cast his Nevada electoral vote for Romney, if the former Massachusetts governor wins the state. Eastman said he wants to explore options with Republican leaders in Clark County, a group now dominated by Paul supporters.

‘‘I'm undecided at this point,’’ Eastman said, adding that he’s ‘‘pretty disgusted’’ with the national Republican Party and how it has worked to suppress Paul’s grassroots movement. He said the GOP has not been open to an influx of people with different ideas.

In Texas, elector Billie Zimmerman said she sees Paul as the only candidate able to save the country. She considers Romney and running mate Paul Ryan to be just another couple of Republicans who will disappoint her, and she called the GOP convention a ‘‘shocking display of deception and treachery and cheating.’’