Joe Biden would be 74 years old the day he was sworn in in 2017 if he won the presidency. That would make him the oldest president in US history, beating Ronald Reagan by nearly 5 years. So, is he serious about running in 2016?

Sure looks like it:

Vice President Joe Biden has accepted U.S. Sen. Tom Harkin's invitation to attend his steak fry this year, White House officials told The Des Moines Register this evening.

"It has been a long-standing commitment after the Vice President was unable to attend last year," a spokesperson in the office of the vice president said.

The annual steak fry is one of the largest Democratic Party events of the year in Iowa and has a long history of attracting top national political figures - especially presidential aspirants. At the 2007 steak fry, six people shared the stage: Biden, Barack Obama, Hillary Clinton, Chris Dodd, John Edwards and Bill Richardson.

Iowa Democrats had been talking last week about a Biden appearance at this year's steak fry (the 36th), but Harkin staffers couldn't confirm the visit at that time. The New York Times broke the news tonight.

On Friday, the only confirmed speaker was San Antonio Mayor Julian Castro. The event will be held Sunday, Sept.15, in Indianola.

Although Clinton is considered Democrats' current popular favorite to become the eventual presidential nominee for 2016, one top Democrat in Iowa said he's certain she's not the only prospect.

Iowa Senate Majority Leader Mike Gronstal told the Register last month that during the Obama inauguration festivities in January, he was invited to a get-together in a tent on the lawn of the vice president's home.

"I don't know why, but there seemed to be an awful lot of people from Iowa there and an awful lot of people from New Hampshire there. I heard some folks who talked with a little bit of a southern drawl and I said, 'Where are you guys from?' and they said, 'South Carolina,'" Gronstal said. "I'm not sure why people from all the early states were massively over-represented at a Joe Biden event."

It might be that Biden hasn't fully decided to run but wants to keep his options open. That's not a bad idea. Therer is already grumbling from some Democrats about talk of Hillary being a sure thing. The "Stop Hillary" faction will be looking for a candidate that could realistically challenge her. Biden has the contacts and could probably raise plenty of cash to make a race of it - at least in Iowa and New Hampshire.

But Biden also has a tremendous downside; he's not very bright, is gaffe prone, and hasn't done anything in the Obama administration. You would think that anti-Hillary Democrats could find a better candidate but at this point, there's no one with the stature in the party to challenge Clinton.