The coming of summer heat in a presidential election year always brings the speculation about potential running mates to a boiling point. Mitt Romney is looking for one now. History suggests a decision could come any time between now and the Republican convention.
The candidate wants to make the most of the announcement and get the most attention possible. But making too much of a splash has its own perils.
A hasty vetting process in 2008 by John McCain and his team led to the selection of Sarah Palin -- seen by some as a political superstar, but by others as a vice presidential nominee with little national name recognition and a thin resume. This time around, Republicans say the Romney campaign will be more deliberate. Some are even promising this will be the most intrusive, thorough vetting process ever.
Romney appears to have begun the process with a series of "try-outs" -- campaign appearances by the candidate with the likes of Marco Rubio, Chris Christie, Tim Pawlenty, Bob McDonnell, Kelly Ayotte and Rob Portman, each appearance producing a flurry of reporting dissecting the pros and cons of each potential running mate.
There is a well-publicized list of Republicans thought to be on Romney's short list. ABC's Jonathan Karl has been handicapping the field.
Meanwhile, here's a look back at vice presidential selections since 1988: who was picked and how it happened.
|1988: Dan Quayle (R)|
The Republican Nominee: Vice President George H.W. Bush ran virtually unopposed to be the Republican standard bearer, having locked up the nomination largely with the support of President Reagan. Bush picked a top team of inner-circle republicans to run his VP search. At the top of the Bush search team were Jim Baker and Jim Cicconi.
The Pick: Senator Dan Quayle of Indiana
The Timing: Tuesday August 16 -- day two of the Republican Convention.
|1988: Lloyd Bentsen (D)|
The Democratic Nominee: Gov. Michael Dukakis of Massachusetts
The Pick: Sen. Lloyd Bentsen of Texas. Dukakis compared his choice to John F. Kennedy's selection of Lyndon B. Johnson in 1960.
The Timing: July 13 in Boston, five days before the convention.
|1992: Al Gore (D)|
The Democratic Nominee: Governor Bill Clinton of Arkansas
The Pick: Sen. Al Gore of Tennessee. Casting aside decades of conventional political wisdom that required balancing and diversifying the ticket, Clinton picked a fellow Southerner. "We share a common philosophy that it's time to move beyond old ideas," Clinton said as he introduced Gore.
The Timing: July 9 -- Four days before the Democratic National Convention.
|1996: Jack Kemp (R)|
The Republican Nominee: Senator Bob Dole of Kansas
The Pick: Former Housing Secretary Jack Kemp of New York
The Timing: August 10 -- Two days ahead of the Republican National Convention.
|2000: Dick Cheney (R)|
The Republican Nominee: Governor George W. Bush of Texas. Bush had asked Cheney, a former Congressman, White House Chief of Staff and Secretary of Defense, who was now the CEO of Halliburton Company, to head up his VP search.< p>
The Pick: Cheney.
The Timing: July 25 -- Six days before the Republican National Convention.
|2000: Joe Lieberman (D)|
The Democratic Nominee: Former Vice President Al Gore.
The Pick: Senator Joe Lieberman of Connecticut. Lieberman became the first Jewish candidate on a major party ticket.
The Timing: August 8 -- Six days before the Democratic National Convention.
|2004: John Edwards (D)|
The Democratic Nominee: Sen. John Kerry of Massachusetts
The Pick: Sen. John Edwards of North Carolina
The Timing: July 6 -- twenty days before the Democratic National Convention. Kerry announced Edwards as his pick in an email to his supporters and then followed up with a speech introducing him at a campaign stop in Pittsburgh.
|2008: Sarah Palin (R)|
The Republican Nominee: Sen. John McCain of Arizona
The Pick:Gov. Sarah Palin of Alaska
The Timing: August 29 -- two days before the Republican National Convention.
|2008: Joe Biden (D)|
The Democratic Nominee: Sen. Barack Obama of Illinois
The Pick: Sen. Joe Biden of Delaware
The Timing: Aug. 23 – Two days ahead of the Democratic National Convention. Obama introduced Biden as his running mate at a rally in Springfield, Illinois.
-ABC's Ann Compton contributed to this report.