George Montgomery (D-IL) was a senator from Illinois. He attended Ellie Bartlet and Vic Faison's wedding, where he criticized Josh Lyman because he hadn't put more money into Illinois after their unexpected surge in the polls there. He called President Bartlet to complain too.
Barry Goodwin called him a blowhard, but he believed that if Congressman Santos had been in Illinois, the cost would have been offset by an increase in fundraising. Leo McGarry called Montgomery out because he hadn't fought for an increased presence in Illinois before the surge and said he was only speaking with the benefit of hindsight.
Montgomery and Goodwin both tried to convince Santos and Leo that Leo should take over as campaign manager, but Leo refused and convinced Santos to stand by Josh.