"There are quite a few names in the top 70 that you may not have heard of or often encountered," said VoteWatch's Doru Frantescu.

Among them is Spanish socialist Ines Ayala Sender, who ranks seventh in a list of 70 MEPs. Other unknowns at the top include Polish conservative MEP Ryszard Czarnecki, Latvian centre-right MEP Krisjanis Karins, and Bulgarian liberal Iskra Mihaylova.

"They are not that well known, they are not very well visible in the media but still they are influential," noted Frantescu.

The more obvious heavy-hitters still dominate with the EU parliament's president, Antonio Tajani, ranking in first place.

Italian socialist group leader Gianni Pittella and German centre-right group leader Manfred Weber share the second spot, followed by the liberal group leader, Belgian MEP Guy Verhofstadt.

Weber's centre-right EPP group is larger than Pittella's socialist S&D. But S&D's smaller size was compensated by the socialists having won more votes in the plenary than the EPP, says VoteWatch.

Despite having lost Martin Schulz, the former EU parliament president, the Germans still dominate - with large delegations in both the EPP and S&D groups.

Their numbers mean they are able to jockey for key positions and take the lead, or so-called rapporteur positions, on policies floated by the European Commission. German MEPs chair five committees in the parliament.

The Italians are also able to squeeze more influence than their French counterparts. Italians have the largest delegation in the S&D, but also manage to exert pressure in fringe groups.

VoteWatch says the flexibility among the populist Five Star Movement's MEPs in the Europe of Freedom and Direct Democracy group means they are able to secure coalitions with other groups and obtain key positions. Earlier this year, the Five Star Movement's MEPs almost joined the liberal group.

It also sets the Italians apart from the French, whose biggest delegation is represented by MEPs from the more narrow National Front party. Fewer more conventional French MEPs leaves them "vulnerable in their own political groups," said Frantescu.

While the British may have dropped influence, given their eventual exit from the European Union, there are exceptions.

Among them is Claude Moraes, a socialist MEP from the UK, who chairs the parliament's civil liberties committee. Moraes ranks sixth in the list.

"It is a fantastic achievement by him to still remain influential but he's an exception to the rule," noted Frantescu.

VoteWatch drew its findings by weighing some 200 responses of people who often interact with MEPs.

It says it used an algorithm that calculates the influence of an MEP on the basis of legislative activity, leadership, and other activities - such as number of amendments.

Its first report was issued last year, and drew similar conclusions.