Mitt Romney said Wednesday that he had not yet picked a vice presidential candidate, but his eventual choice would be a "conservative."

His words added a new twist to Washington favorite parlor game of recent weeks: who will Romney pick and when will people find out who it will be?

While Romney has given no indication of a particular name, he has sought to reassure the party's base that they will be satisfied with his decision.

His latest response came as a supporter at a town hall in Ohio asked him for assurances that he would choose someone who would stand up for conservative ideas in elections to come.

"I can assure you that even though I have not chosen the person that will be my vice president, that person will be a conservative, they will believe in conservative principles," Romney told the woman.

Romney has worked in recent days to tamp down on speculation about his choice of running mate, while reassuring the right-wing of the party. When former Secretary of State Condoleezza Rice surfaced in a piece from the Drudge Report last week, some Republicans argued her support of abortion rights stance should preclude her from nomination. Romney has said on previous occasions he would pick a running mate who opposed abortion rights.

Lately, speculation has centered around former Gov. Tim Pawlenty (R-Minn.), Sen. Rob PortmanRobert (Rob) Jones PortmanSenate moving ahead with border bill, despite Trump 13 GOP senators ask administration to pause separation of immigrant families Lawmakers, businesses await guidance on tax law MORE (R-Ohio) and Louisiana Gov. Bobby Jindal — any of whom would likely satisfy the right.

During an interview set to air Thursday with ABC News, Romney's wife, Ann, said Romney's eventual pick would share many of her husband's qualities.

"I was thinking of passion for this country, being able to serve, being able to have experience, real experience, being able to be ready Day One," Ann Romney said. "Actually, if you think about it, there's a lot of people that fit under that umbrella."

But Ann Romney added that she did not know when an announcement would be made — and her husband provided no additional insight on Wednesday. The campaign has only said that a choice will be revealed before the Republican convention begins on Aug. 27 in Tampa.