While an Article V Convention has never been held, looking at the history surrounding Constitutional amendments, it is clear that the states making calls for one play a major role in getting them passed. The 10 amendments of the Bill of Rights as well as the 27th Amendment, which was ratified much later, were proposed in part due to Article V convention calls by Viriginia and New York, which were among the most powerful of the 13 original states, and 4 other amendments since also involved calls on the subject (the 17th, 21st, 22nd, and 25th). This means that a majority, 15 of 27, of all amendments have been enshrined into the Constitution due to states promising to move forward when Congress would not, forcing Congress to take notice and, eventually, action, even when they have strong incentive not to.
The most notable example of this was the 17th Amendment. At the time, the selection of Senators by state legislatures was widely seen as undemocratic, and the Senate itself as a millionaires’ club beholden to special interests. The House passed several resolutions proposing amendments to allow for the direct popular election of Senators, but the Senate staunchly refused to consider them. In response, the states began submitting applications for an Article V Convention, and when they were a just a couple shy of the 2/3rds threshold, the Senate caved, and the amendment was passed.
While the position of Delaware Get Money Out is that an Article V Convention is the way to go considering how unlikely it is that Congress will propose an amendment dealing with money in politics, it really doesn’t matter where the amendment comes from. Having the states just make the calls for a convention puts immense pressure on Congress and is a proven method of getting Congress to propose amendments themselves, unlike petitioning its members directly.