Senator Chuck Grassley plans to pick a 2012 presidential candidate with “staying power” but won’t make a public endorsement before next month’s Iowa Republican Party Straw Poll. Grassley says his endorsement “may” come in October.

“I would have given you that same answer in January and as we get closer to October and we still have people that maybe aren’t in the race like there’s still talk about Palin; there is about Perry; there was talk about the former mayor of New York, you know?” Grassley said during a radio interview. “So I want to wait ’til everybody gets in before I make up my mind.”

Grassley stayed out of the 2008 endorsement sweepstakes, but his 1996 endorsement of Kansas Senator Bob Dole helped Dole stiff-arm the competition during that Iowa Caucus campaign. This past March, Grassley said “only two or three of the candidates” who were actively campaigning at that time were qualified to be president. Now, four months later, Grassley points to the performance of the seven Republican candidates who debated in New Hampshire last month .

“Almost any one of those people could beat President Obama,” Grassley says. Grassley suggests Obama’s Achillies Heel is the economy.

“President Obama, for a long period of time, was blaming President Bush for what he inherited and he didn’t inherit a very good situation, I’d have to admit,” Grassley said. “But if you look at every statistic that measures the economy whether its unemployment or interest rates or the budget deficit or the national debt or housing prices going down or anything else — if you look at any of those, what they were on January the 20th 2009 when this president was sworn in, this president has made every one of those worse.”

Grassley is the senior Republican official in Iowa. He was first elected to a seat in the state legislature in 1958. He won a seat in the U.S. House in 1974 and has been serving as a U.S. senator since 1981.

(Reporting in Cedar Falls by Jesse Gavin of KCNZ Radio; editing by Radio Iowa’s O. Kay Henderson)