Voters concerned about gridlock in Washington want to know if a presidential candidate is going to be able to take a bipartisan approach to resolving the nation's problems.

So on the campaign trail in Iowa, Democrat Hillary Clinton said she could work with Republicans because that's what she did when she served in the U.S. Senate from 2001 to 2009.

"When I was in the Senate, of course I had to work with Republicans. I think every piece of legislation, just about, that I ever introduced had a Republican co-sponsor," she said at a campaign organizing event in Toledo, a small town between Des Moines and Cedar Rapids.

PolitiFact, which is in Iowa this week covering the caucuses, wanted to see if Clinton had that right.

We used GovTrack.us to see any Republican senator who co-sponsored a bill by Clinton. Of the 355 bills she sponsored that were referred to a Senate committee, Republicans were listed as a co-sponsor 241 times. That means, in theory, up to 68 percent of Clinton’s bills could contain a Republican co-sponsor.

But the real percentage is likely much lower.

Sen. Robert Bennett, R-Utah, for instance, co-sponsored six pieces of Clinton legislation. Four of those pieces of legislation had 10 or more Republican co-sponsors.

We also did a spot check of Clinton’s record by looking at legislation directly.

Congress.gov is the official website for U.S. federal legislative information. It says that Clinton sponsored 703 pieces of legislation while representing New York. They include bills, amendments and resolutions. We sorted the list by "Latest Action - Newest to Oldest" and then spot-checked every 10th bill, starting with the Paycheck Fairness Act , to see which ones had at least one Republican sponsor.

From that list, we focused on the 44 pieces of legislation that were introduced, the term Clinton used.

We found at least one Republican co-sponsor in 4 of 7 resolutions or continuing resolutions (57 percent) but only 9 of 37 bills (24 percent).

Overall, that's 13 out of 44, or just under 30 percent.

Focusing on the 18 bills that Clinton sponsored and brought to the Senate floor for consideration, four had at least one Republican co-sponsor (22 percent):

• A bill commemorating the 225th Anniversary of the American Revolution Commemoration Act (two GOP co-sponsors);

• A bill dealing with respite care (four GOP co-sponsors);

• A bill concerning the labeling of pediatric medication (two GOP co-sponsors);

• A bill seeking to assist the victims of landmines (four GOP co-sponsors).

So neither metric supports Clinton’s claim.

None of this is to say she didn’t work with Republicans during her time in the Senate.

But if someone says, as Clinton did, that "Just about every piece of legislation I introduced had a Republican co-sponsor," we think most listeners would expect better than 30 percent of the legislation introduced by Clinton would include a GOP co-sponsor.

When we heard back from the Clinton campaign, spokesman Josh Schwerin said, "She meant to say, 'Just about every Republican senator I served with co-sponsored a piece of legislation I introduced.'"

"In total, 57 (Republican) colleagues cosponsored at least one piece while only 8 did not," he reported in an email, and Schwerin supplied a list of 42 pieces of legislation to support that assertion. The list can be viewed here .

However, that claim is a significantly different from what voters heard in Iowa on Jan. 18.

Our ruling

Clinton said, "Every piece of legislation, just about, that I ever introduced (in the U.S. Senate) had a Republican co-sponsor."

By our review of legislation introduced by Clinton, she isn't even close.

Her campaign says she meant to cast the statement differently, but we cannot rule based on what candidates intended to say. Clinton introduced a significant amount of legislation without Republican co-sponsors.