WASHINGTON (AP) - A Senate Intelligence Committee member says Hillary Clinton's campaign chairman and the former Democratic Party head need to explain what they knew about a dossier of allegations about President Donald Trump's ties to Russia.

Maine Sen. Susan Collins says the committee should further question John Podesta and Debbie Wasserman Schultz following disclosures last week that the Clinton campaign and DNC helped fund research that ended up in the dossier.

Collins tells CBS' 'Face the Nation" that "it's difficult to imagine" that Podesta didn't know about the funding.

FILE - In this March 21, 2016, file photo, attorney Marc Elias, one of several lawyers who appeared in the in the case of Wittman v. Personhuballah, stands on the plaza of the Supreme Court in Washington. Hillary Clinton's presidential campaign and the Democratic National Committee helped fund a political research firm that produced a dossier of allegations about President Donald Trump's ties to Russia. That's according to a person familiar with the situation who spoke on Oct. 24, 2017, to The Associated Press. The person says the arrangement, first reported by The Washington Post, was coordinated by a lawyer for the campaign and the DNC and his law firm. That lawyer, Marc Elias, did not immediately return an email seeking comment. (AP Photo/J. Scott Applewhite)

Podesta and Wasserman Schultz last month denied knowledge about payments when interviewed by congressional investigators. Sitting next to Podesta was his attorney Marc Elias, who worked for the law firm that brokered funding, CNN reported.

Collins says Elias should also be questioned.