In all likelihood, most voters in Louisiana and Virginia aren't either. [...] yet Democratic Sen. Mark Warner is talking about the bank on the campaign trail, portraying it as a job creator that must be protected against tea party ideologues. Voters are likely to hear the same message from other Democratic senators seeking re-election this fall, including Louisiana's Mary Landrieu, who like Warner made the bank the focal point of a campaign event Monday. The Ex-Im Bank provides loans, loan guarantees and credit insurance to foreign buyers of U.S.