There isn't a damn thing wrong with what the Democratic platform currently says. It calls for a two-state solution for gosh sake. What do they want to change? I suspect it will be something like "return to the 67 borders, or right of return, which is code word for the elimination of Israel". None of that will happen in the Democratic platform, nor should it. Any specific demands need to be negotiated by the respective parties, the Israelis and Palestinians, and not part of the Democratic platform.
It is this paragraph in the current Democratic platform that sets up the foundation for a negotiated settlement:
"It is precisely because of this commitment that President Obama and the Democratic Party seek peace between Israelis and Palestinians. A just and lasting Israeli-Palestinian accord, producing two states for two peoples, would contribute to regional stability and help sustain Israel's identity as a Jewish and democratic state. At the same time, the President has made clear that there will be no lasting peace unless Israel's security concerns are met. President Obama will continue to press Arab states to reach out to Israel. We will continue to support Israel's peace treaties with Egypt and Jordan, which have been pillars of peace and stability in the region for many years. And even as the President and the Democratic Party continue to encourage all parties to be resolute in the pursuit of peace, we will insist that any Palestinian partner must recognize Israel's right to exist, reject violence, and adhere to existing agreements."
https://www.democrats.org/party-platform#strengthening-alliances
Seven in 10 Americans Continue to View Israel Favorably
http://www.gallup.com/poll/181652/seven-americans-continue-view-israel-favorably.aspx